Sofa



FIG. 1 is a perspective view of a sofa showing my new design taken from the front and one side;

FIG. 2 is a front view thereof;

FIG. 3 is a side view thereof, taken from the side opposite said one side;

FIG. 4 is a top plan view thereof; and

FIG. 5 is a rear view thereof.

The underneath of the sofa is not ornamented. 

The ornamental design for a sofa, as shown and described. 